Adobe is offering Adobe Creative Cloud, with subscription based access to download Adobe's entire CS6 Master Collection (including Lightroom 4), at a $20 discount for $29.99/month (1st year only). Valid only for existing CS product owners. After the first year, the the price rises to $49.99 monthly. This offer has been extended to 6/1/2013 and is valid for current CS owners.

Update:: Students Get Adobe Creative Cloud for only $19.99/month. (Exp 11/4)
This is an incredible deal, since the entire CS6 Suite goes for around $2,500. If you compared the price of buying the entire suite to the monthly subscription (at the full $49.99), it would take you about 4-years (51-months) to break even, at which point there would likely be another version if not two updates already available.

Now for a limited time. With a Cloud subscription you also get access to the FULL PERMANENT version of Adobe Edge Animate 1.0 ($499 value). Read more about it HERE.